Star Trek tractor beam effect
This  is written for Cycles, however the same steps apply for Blender Internal except you do not need the volume mesh. All steps including the shadow mesh and lamps are the same.



I would recommend using a cone shaped mesh set to volume, a mesh that has holes in it to give the beam shadow, and a spot lamp. Start by adding a cone to your scene using Shift+A > Mesh > Cone:



Now move it, scale it, etc. as desired and add a spot lamp using Shift+A > Lamp > Spot and move it to the top of the cone.



Now change the cone material to have a Transparent surface material and a Volume Scatter volume material in the material settings:



Now all you need to do is add the texture to the volume. I do this by adding a plane, subdividing, and then deleting some random vertices:



Now move it into the beam of light, rotate, duplicate, etc. and tweak the lamp settings and position as desired. You should end up with a result like this:



I have included the .Blend file for you to examine and compare with.